login
This site is supported by donations to The OEIS Foundation.
Logo

Hints
(Greetings from The On-Line Encyclopedia of Integer Sequences!)
A143150 A triangle sequence based on the Folium of Descartes implicit: x^3+y^3-3*a*x*y: t(n,m)=n^3+m^3-3*n*m. 0
-1, 3, 4, 19, 17, 27, 53, 48, 55, 80, 111, 103, 107, 129, 175, 199, 188, 189, 208, 251, 324, 323, 309, 307, 323, 363, 433, 539, 489, 472, 467, 480, 517, 584, 687, 832, 703, 683, 675, 685, 719, 783, 883, 1025, 1215, 971, 948, 937, 944, 975, 1036, 1133, 1272, 1459, 1700 (list; graph; refs; listen; history; internal format)
OFFSET

1,2

COMMENTS

Row sums are:

{-1, 7, 63, 236, 625, 1359, 2597, 4528, 7371, 11375}.

REFERENCES

Smamuel M. Shelby, ed., "CRC Standard Mathematical Tables and Formulae", 12th Edition, Curves and Surfaces (page 421),

FORMULA

t(n,m)=n^3+m^3-3*n*m.

row sums: sum_{m=1..n} t(n,m) = n^2*(5n^2-4n-5)/4 . [From R. J. Mathar (mathar(AT)strw.leidenuniv.nl), Oct 24 2008]

EXAMPLE

{-1},

{3, 4},

{19, 17, 27},

{53, 48, 55, 80},

{111, 103, 107, 129, 175},

{199, 188, 189, 208, 251, 324},

{323, 309, 307, 323, 363, 433, 539},

{489, 472, 467, 480, 517, 584, 687, 832},

{703, 683, 675, 685, 719, 783, 883, 1025, 1215},

{971, 948, 937, 944, 975, 1036, 1133, 1272, 1459, 1700}

MATHEMATICA

Clear[t, n, m]; t[n_, m_] = n^3 + m^3 - 3*n*m; Table[Table[t[n, m], {m, 1, n}], {n, 1, 10}]; Flatten[%]

CROSSREFS

Sequence in context: A089427 A197564 A020344 * A100340 A042175 A041703

Adjacent sequences:  A143147 A143148 A143149 * A143151 A143152 A143153

KEYWORD

uned,sign

AUTHOR

Roger L. Bagula and Gary W. Adamson (rlbagulatftn(AT)yahoo.com), Oct 17 2008

Lookup | Welcome | Wiki | Register | Music | Plot 2 | Demos | Index | Browse | More | WebCam
Contribute new seq. or comment | Format | Transforms | Puzzles | Hot | Classics
Recent Additions | More pages | Superseeker | Maintained by The OEIS Foundation Inc.

Content is available under The OEIS End-User License Agreement .

Last modified February 16 18:54 EST 2012. Contains 205939 sequences.